textproduct: Albany

WHAT HAS CHANGED

Increased wind gusts for today and for Sun P.M into Sun night. We will continue to monitor trends and decide if a wind advisory is needed Sunday night, highest chance is in the northern Taconics and northern Berkshire County.

Expanded footprint of wintry mix including both sleet and freezing rain for tomorrow evening to include more the Mohawk Valley and valley areas mainly north of Albany. As said in previous discussion, confidence continues to increase that we will need a winter weather advisory for slippery travel for at least the hill towns and higher terrain areas of eastern NY and western New England.

Increased POPs a bit for Sunday night in the southwest Adirondacks, Mohawk Valley, northern Catskills, northern Taconics, southern Greens and northern Berkshire County where lake effect and upslope snow showers are favored. Still only expect light snow accumulations ranging 1 to 3 inches.

Ice jam flooding potential remains low. Additional information in the hydro section.

KEY MESSAGES

- Potential for slippery roads and walking surfaces late tonight into early Saturday morning as wet surfaces from snow melt and rain showers may turn slick from temperatures falling towards freezing late tonight and winds turning lighter. Highest chance in the Upper Hudson Valley. - Slippery road conditions tomorrow night within the Southwest Adirondacks, northern/eastern Catskills, Helderbergs, Berkshires, Taconics, Berkshires, and Southern Vermont due to light ice accumulations from freezing rain and light snow/sleet accumulations. Winter Weather Advisories will likely be needed where confidence is highest for freezing rain. - Increasing confidence for strong wind gusts reaching 35-45mph Sunday afternoon into especially Sunday night. Such strong winds can lead to downed tree limbs and blow around unsecured outdoor objects. There is a low chance that we will need a wind advisory in the Rensselaer Plateau and northern Berkshire County.

DISCUSSION

KEY MESSAGE 1...

A tightening sfc pressure gradient ahead of an incoming occluded front this afternoon has resulted in gusty winds reaching 25 to 35mph with a few gusts nearing 40mph in the higher terrain. Despite an impressive 45-55kt jet in the 925-850hPa layer, a strong low-level inversion seen on forecast soundings is likely prohibiting these stronger winds from reaching the sfc. Temperatures have warmed up nicely ahead of the front as well with many in the low to mid-40s. The mild air combined with the gusty winds has aided snow melt as well. As showers continue to overspread the region from west to east this afternoon, the gusty winds will gradually weaken with showers exiting into New England early this evening. After a brief lull, the main trough axis and cold front will track across northern New England tonight, resulting in a second batch of rain showers this evening through about Midnight. When all is said and done, only expecting a few hundredths up to a tenth of an inch of rain in valley areas with a tenth up to 0.25" of an inch elsewhere. The south facing slope of the southern Adirondacks will be locally higher up to 0.25 to 0.50" due to upslope enhancements. Most rain showers exit by Midnight with winds remaining a bit breezy reaching 5-10mph in the Mohawk Valley, Capital District into western MA but even lighter winds in the Upper Hudson Valley and mid-Hudson Valley.

Between daytime temperatures supporting snow melt plus incoming rain showers this afternoon/evening, it is possible that some roads and walkways could become slick from standing water that turns into black ice by early tomorrow morning as temperatures fall into the low 30s. Highest confidence in the Upper Hudson Valley where winds will be lighter.

KEY MESSAGE 2...

A 1025hPa high builds into western Quebec tomorrow morning as our cold front settles into the mid-Atlantic with east to northeasterly winds advecting a cooler air mass into the Northeast. Temperatures will be slightly cooler in comparison to Friday but still running a bit milder for mid-January standards with high temperatures in the upper 30s to low 40s. The sfc high and shortwave ridging building overhead will keep us dry through much of the day; however, a deepening closed low over the Great Lakes will enhance the southwesterly jet in the low and mid-levels and send the stalled front in the mid-Atlantic northward as a warm front. Increasing isentropic lift early tomorrow evening will allow precipitation to spread from south to north and while initial temperatures will be mild in the mid to upper 30s supporting mainly rain, wet-bulb cooling processes will allow sfc temperatures to cool, especially in the higher terrain and hill towns. This will likely allow a transition to a wintry mix including both sleet and freezing rain as southwesterly winds aloft maintain a warm nose aloft. The latest guidance continues to suggest a secondary coastal low develops off the coast of Long Island which may pinch off the warm nose aloft and reduce the moisture influx and thus keep overall shower coverage and intensity rather light through much of the evening hours.

As the parent low tracks further east and the triple point advances further east, a second area of showers likely overspreads the region overnight. However, the warm nose looks to erode and exit further to our east as we approach the pre- dawn hours on Sunday which should reduce the potential for sleet/freezing rain and support mainly rain/snow mix overnight. Strong southwest flow ahead of the parent low will direct a dry slot into the Northeast by Sunday morning, putting an end to most of the wintry precipitation. When all is said and done, this still appears to be a minor event with only a coating up to an inch or so of snow/sleet as well as a glaze up to 0.10-0.15" of flat ice from periods of freezing rain mainly in the southwest Adirondacks, southern Greens, Mohawk Valley, Upper Hudson Valley, northern/eastern Catskills, and the Taconics/Berkshires Sunday night. Although overall accumulations are expected to remain low, even light amounts of wintry mix can result in slippery travel, especially in the hill towns and higher terrain where sfc temperatures should be cooler. Winter Weather Advisories will likely be needed where confidence is highest for freezing rain.

KEY MESSAGE 3...

Most of Sunday will be dry yet breezy as the dry slot overspreads the Northeast and steepens mid-level lapse rates supporting wind gusts 20-30mph. However, tempertures will remain seasonably mild in the mid to upper 30s as we remain within the southwest flow regime. Once the main trough axis swings through Sunday evening into especially the overnight hours, cold air advection will commence and temperatures will turn cooler. Not only will lapse rates and overall boundary layer mixing steepen further supporting stronger wind gusts, we will also monitor a lake effect snow response developing off Lake Ontario. Latest probabilistic guidance shows greater than a 75% chance for wind gusts to exceed 30mph across eastern NY and western New England during the 24hr window from 1AM Sun to 1AM Mon. In fact, there is even a 50 to 75% chance for wind gusts to exceed 40mph mainly from the Capital District eastward the Taconics and western MA during this time. Should confidence in wind gusts exceed 45mph increase, a wind advisory may be needed with the highest chance in the Rensselaer Plateau and northern Berkshire County.

Lake effect snow showers look to be directed mainly in the southwest Adirondacks, Mohawk Valley, northern Catskills with upslope snow showers developing in the southern Greens, northern Taconics and northern Berkshires. However, as wind veer to the northwest overnight Sunday, a less favorable fetch will weaken lake effect showers while upslope snow showers should still continue in western New England. Overall, this looks to be a light event with latest guidance limited probabilities for at least 2" of snow to just the western Adirondacks where there is a 30 to 70% chance and the southern Greens where values are less than 10%.

AVIATION /00Z SATURDAY THROUGH WEDNESDAY/

Through 00z/Sun...MVFR stratus is in place at all TAF sites ahead of an approaching cold front. Brief IFR stratus could occur at some sites prior to the cold front with the higher confidence at KPSF. A few light rain showers will accompany the cold front (between 1-3z/Sat), though the light nature should result in minimal visibility reductions (maybe to MVFR). Behind the cold front, clouds will begin to partially break with a gradual return to VFR cigs expected (except at KPSF where MVFR cigs likely linger through the night).

VFR conditions will then continue for much of Saturday before clouds thicken and lower after 18z/Sat as precipitation within a warm front approaches from south to north. Rain or mixed precipitation will begin from south to north between 20-24z/Sat. Cigs and or vsbys could lower to MVFR at some sites to even IFR at KGFL if precipitation begins as snow.

South to southwesterly winds with occasional gusts to around 20 kt will shift to the west to northwest behind the cold front at similar speeds. Winds will decrease to less than 10 kt later tonight and through much of the day Saturday at variable directions. Periods of LLWS will continue at all TAF sites prior to the cold front with winds at 2000 ft between 40-45 kt.

Outlook...

Saturday Night: High Operational Impact. Definite RA...SN. Sunday: Moderate Operational Impact. Chance of RA. Sunday Night: Low Operational Impact. Breezy. Slight Chance of SHSN. Monday: Low Operational Impact. Breezy. NO SIG WX. Monday Night: No Operational Impact. NO SIG WX. Tuesday: No Operational Impact. NO SIG WX. Tuesday Night: Low Operational Impact. Slight Chance of SHRA. Wednesday: Moderate Operational Impact. Chance of SHRA.

HYDROLOGY

While we remain in an above normal temperature pattern for much of the next week, temperatures will not become warm enough to pose major break-ups of river ice. Additionally, despite the rainfall and snowmelt that we are anticipating this weekend, river forecasts only show an approach to Action Stage at most. Therefore, ice jam flooding is not anticipated.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.